Analysis of the cogging process for heavy ingots by finite element method and physical modelling method

For a design of the cogging processes to obtain sound forgings of the monoblock rotor, the effects of forging parameters have been investigated. Parameters such as die configuration, die width and reduction of height have been considered in the design of the process. The three-dimensional finite element analysis is carried out for the cogging processes in order to study the distribution of effective strains, hydrostatic stresses and axial stresses. Physical modelling of 1/40th scale using plasticine modelling clay is performed to verify the results of simulation and to design the process. Optimal working conditions of heavy ingots are suggested for defect-free product quality. (C) 1998 Elsevier Science S.A. All rights reserved.